1) Look
at the primary coverts - on HY/SY birds they are
brownish and contrast visibly with the black
greater coverts, while on AHY/ASY birds they are
blackish and uniform in colour and wear with the
greater coverts

3) In
spring look at the face - males have a
black mask, while females have a gray face

4)
Examine r2 (the second rectrix from the centre) -
on AHY/ASY males the white spot is similar in size
to that on other rectrices, on AHY/ASY females and HY/SY
males the white spot is slightly to moderately
smaller than on other rectrices, and on HY/SY
females the white spot is absent or considerably
smaller than on other rectrices

Second-year males have a black mask just
like after-second-year males, but tend to have somewhat less black on the back.
Nonetheless, the wing and/or tail should be checked to confirm age.
Sometimes contrasts between the retained brownish juvenile feathers and replaced black feathers can be seen on the wing when perched, as in the two examples below.

Photos by Marie-Anne Hudson,
McGill Bird Observatory (QC), May 2008

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), May 2006

Note in both photos below the considerable contrast between the brownish
primary coverts and the black greater coverts, as well as the narrow and
pointed shape of the outer primary coverts. The extent of
replacement of the greater coverts is somewhat variable, as reflected by
the second photo in which the outer greater coverts are faded and worn;
nonetheless the primary coverts remain diagnostic, especially when
compared to the inner greater coverts.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), May 2006

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), May 2006

The photo below shows a fairly typical second-year male tail, with
relatively narrow and pointed rectrices, and a moderately large white
patch on r2 that is only a bit smaller than the patches on the outer
four rectrices. The second photo illustrates that shape can be somewhat less reliable for this species than some other warblers.

Second-year females lack a distinct facial mask and have
less spotting on the breast than males. Sometimes second-year
females can be recognized when perched by their brownish primary
coverts, but the contrast is more subtle on them than on males, and
closer examination of the wing and tail is recommended.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), May 2005

Photo by Marie-Anne Hudson,
McGill Bird Observatory (QC), May 2007

This pattern in the photo below is fairly typical of a second-year
female wing, with dark gray to blackish greater coverts noticeably
darker than the grayish-brown primary coverts, the outer ones of which
are narrow and pointed (the primary coverts are often somewhat more
brownish, as in the second photo). Unreplaced and somewhat worn
tertials (as in the second photo) are also a good indicator of second-year birds of either sex.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), May 2005

Photo by Marie-Anne Hudson,
McGill Bird Observatory (QC), May 2007

The rectrices are relatively narrow and pointed toward the tip, though
not as much so as on some other small passerines. However, note
that on r3 the white spot is often reduced and on r2 it is still smaller or entirely absent.

In summer and early fall, some
after-hatch-year Magnolia Warblers can be aged as second-year if they
have retain juvenal feathers, which are particularly faded and worn by
this time. Such a bird can often be identified as such even in the
field - for example, in the photo below, some pale brown unreplaced
secondaries are visible.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2005

The presence of unreplaced juvenal feathers on the
wing is much easier to see on the photos below. In the upper
photo, the outer secondaries are growing in, replacing the very faded
and worn juvenal inner secondaries. The bird in the lower photo
was caught a bit earlier in the moult cycle, with the outermost primary
coverts and primaries still unreplaced juvenal feathers, and only the
outermost secondary replaced so far.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2005

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2005

The tail is likely to
be of little value in identifying a Magnolia Warbler as second-year, as
the individuals that have been caught in moult at MBO have replaced
their tail prior to completing their wing moult.

After-hatch-year
birds are recognizable by their uniformly dark wings; females have a
somewhat paler overall plumage than females (more grayish than
blackish), but wing and tail should be examined to be confident of sex
in fall.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2008

On after-hatch-year
females, the primary coverts may be a slightly lighter shade of dark
gray than the greater coverts, but they are uniform in wear, and the
outer primary coverts are broad and rounded.

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2008

The rectrices are fairly
broad until near the tip and generally somewhat rounded, although some
after-hatch-year birds do show a bit of a point as in the example below;
wing features are more reliable. The rectrices tend to be not quite as black as on males.

Hatch-year
birds may show a contrast between primary coverts and greater coverts
when perched, but more often the open wing and tail need to be examined
to assess age and sex.

Photos by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2008

Photo by Marcel Gahbauer,
McGill Bird Observatory (QC), August 2008

On hatch-year Magnolia Warblers, the primary coverts
are a brownish-gray, uniform with the primaries, but contrasting with
the noticeably darker and fresher greater coverts. Sex can often not be
determined, but males tend to be somewhat darker, and in combination
with "male-type" tails it is possible that a significant proportion can
be correctly sexed.

The tail may be
particularly useful in separating hatch-year males and females.
Hatch-year Magnolia Warblers tend to have relatively narrow rectrices that
taper toward a point, but those with particularly dark rectrices and a
white spot on r2 at least 2/3 the size of that on r3 are very likely to
be males; with smaller white patches sex is questionable.

Hatch-year
birds may show a contrast between primary coverts and greater coverts
when perched, but more often the open wing and tail need to be examined
to assess age and sex. Females tend to be paler overall than males, and typically have little or no streaking on the flanks.

On hatch-year Magnolia Warblers, the primary coverts
are a brownish-gray, uniform with the primaries, but contrasting with
the noticeably darker and fresher greater coverts. Sex can often not be
determined, but females tend to be somewhat paler, and in combination
with "female-type" tails it is possible that a significant proportion
can be correctly sexed.

The tail may be
particularly useful in separating hatch-year males and females.
Hatch-year Magnolia Warblers tend to have relatively narrow rectrices that
taper toward a point, but those with very small spots on r3 and r2 (as in the photo below) or entirely lacking white on r2 (as in the second photo) are almost certainly females. Note too
that even on the outer rectrices the white spots are much smaller than
on the hatch-year males shown above, and that the rectrices tend to be grayish rather than blackish. However, some hatch-year
Magnolia Warblers have tails with intermediate characteristics and are
not reliably sexed.